8 Farmers9 Bulletin 1126.

Ariz., the yield of Sudan grass was 7.8 tons per acre, as compared with a yield of 9.8 tons of alfalfa, and at Owens, Ariz., Sudan grass made a yield of 4.5 tons per acre with only one irrigation during the season.

These unusual yields of hay from an annual crop, which by its nature can be made to fit into any rotation, will no doubt mean much to the dairying industry of the Southwest.

The percentage of moisture is apt to be somewhat greater in Sudan grass than in alfalfa when the weights are taken directly from the field, but less labor is necessary to handle the Sudan grass because the maximum yield from it is secured in three cuttings, while with the alfalfa five or more cuttings are required to produce the yields mentioned.

Sudan is the only grass which yields under irrigation in the Southwest even approximately as much as alfalfa. It can be used, therefore, in providing a change of feed without reducing the tonnage obtained from the land. Sudan grass was found just in time to fill this need, and although it is not as rich in protein as alfalfa, experience indicates that when mixed with alfalfa or fed with some concentrate rich in protein the flow of milk will be nearly or quite normal.

SUDAN GRASS AND LEGUME MIXTURES.

The suitability of Sudan grass for growing in mixtures with cowpeas, soy beans, and other legumes in regions to which Sudan grass and these legumes are well adapted is at once apparent. (1) Sudan grass grows strictly erect, with a stem stiff enough to support the vines characteristic of most legumes, and it thus makes the harvesting easier by keeping the legumes off the ground. It also allows them to cure more quickly by preventing the leaves from matting. (2) It is low in protein, which is abundant in the legumes, and thus a wellbalanced mixture is produced. (3) The yields in the humid regions are equal to those of Sudan grass when seeded alone, but the difficulty of getting a good stand and of harvesting the mixture is greater.

Tests of Sudan grass and legume mixtures in the States of Maryland, Virginia (fig. 5), Kentucky, Tennessee, Mississippi, and Louisiana during the 4-year period from 1912 to 1915 gave the following average yields: For Sudan grass and soy beans 2.96 tons, Sudan grass and cowpeas 2.93 tons, and Sudan grass alone 2.67 tons per acre. In dry regions such mixtures are not profitable except when irrigated. If there is insufficient soil moisture to support both the Sudan grass and the legume, the grass almost invariably crowds out the legume. The growing of such mixtures should therefore be attempted only in humid regions or where irrigation is possible.

CULTURE.

PREPARATION OF THE SEED BED.

In seeding Sudan grass a rather firm seed bed is best. Usually when it is desired to drill the seed, the ground is plowed in the spring and harrowed well, as for corn. A cool soil delays the germination of the seed; therefore spring plowing is preferable for the seed bed,